Endocrine Abstracts

JOINT3117

Introduction: Acute suppurative thyroiditis (AST) is a rare but serious bacterial infection of the thyroid gland, accounting for 0.1%-0.7% of thyroid diseases, mainly affecting children and linked to congenital anomalies like pyriform sinus fistulas. These fistulas can serve as a pathway for infection, potentially leading to abscess formation and spreading to adjacent tissues, which renders early diagnosis crucial. Mortality rates range from 3.7%-9%, highlighting the need for prompt treatment. This study reports a rare case of AST caused by a fistula originating from the thyroid gland and extending to the arytenoid fossa.

Case report: A 2 ^10/12-year-old girl with a known thyroid nodule on the left lobe presented with fever for 4 days and painful anterior neck swelling. Palpation revealed a 4×3 cm anterior left sided neck mass with tenderness and erythema of the overlying skin. Laboratory tests showed elevated white blood cell count (25,840/μL), C-reactive protein (CRP) of 146 mg/l and erythrocyte sedimentation rate (ESR) of 85 mm/hr. Thyroid-stimulating hormone (TSH) was 3.51 mIU/l and free-T4 was 1.50 ng/dl (normal range 0.74-1.6). Thyroid ultrasound revealed an isoechoic nodule (42x19x25 mm), occupying almost the entire left thyroid lobe and reactive local lymph nodes. Antibiotic therapy with Cefotaxime and Clindamycin was initiated. ENT examination revealed no signs of an abscess. Fever subsided after four days of intravenous treatment, and neck swelling began to resolve. The patient completed a 10-day course of antibiotics. A follow-up thyroid ultrasound, performed two weeks later, revealed an enlarged nodular area of the left lobe with heterogeneous echotexture, cystic regions, and multiple reactive lymph nodes, consistent with suppurative thyroiditis. This was caused by a fistula originating from the thyroid gland and extending to the arytenoid fossa, confirmed by MRI of the cervical area. Following consultation with both ENT and paediatric endocrinology specialists, conservative 6monthly follow up was suggested. This decision was based on the absence of further episodes of thyroiditis and the lack of indications for surgery.

Conclusions: Acute suppurative thyroiditis is a rare but potentially life-threatening condition if untreated, mainly due to underlying conditions or congenital abnormalities, such as pyriform sinus fistula. Lack of awareness contributes to the delay in adequately treating this rare entity and to frustrating relapses. Treatment typically involves surgery and antibiotics, but recent studies suggest that less invasive approaches may also lead to favourable outcomes. This underscores the importance of balancing expert opinion with evidence-based practices in managing this endocrine emergency.